Fix memory and file descriptor leaks in pg_receivexlog/pg_basebackup

When the internal loop mode was added, freeing memory and closing
filedescriptors before returning became important, and a few cases
in the code missed that.

Fujii Masao

diff --git a/src/bin/pg_basebackup/receivelog.c b/src/bin/pg_basebackup/receivelog.c
index e6c2dec6ef2b65d4742a07cf9d2c9a724b649bad..12b349105578221fe55aac6317d3801d4ec9befb 100644 (file)
--- a/src/bin/pg_basebackup/receivelog.c
+++ b/src/bin/pg_basebackup/receivelog.c
@@ -38,6 +38,10 @@
 #define STREAMING_HEADER_SIZE (1+sizeof(WalDataMessageHeader))
 #define STREAMING_KEEPALIVE_SIZE (1+sizeof(PrimaryKeepaliveMessage))
 
+/* fd for currently open WAL file */
+static int     walfile = -1;
+
+
 /*
  * Open a new WAL file in the specified directory. Store the name
  * (not including the full directory) in namebuf. Assumes there is
@@ -96,6 +100,7 @@ open_walfile(XLogRecPtr startpoint, uint32 timeline, char *basedir, char *namebu
        {
            fprintf(stderr, _("%s: could not pad WAL segment %s: %s\n"),
                    progname, fn, strerror(errno));
+           free(zerobuf);
            close(f);
            unlink(fn);
            return -1;
@@ -120,7 +125,7 @@ open_walfile(XLogRecPtr startpoint, uint32 timeline, char *basedir, char *namebu
  * completed writing the whole segment.
  */
 static bool
-close_walfile(int walfile, char *basedir, char *walname, bool segment_complete)
+close_walfile(char *basedir, char *walname, bool segment_complete)
 {
    off_t       currpos = lseek(walfile, 0, SEEK_CUR);
 
@@ -142,8 +147,10 @@ close_walfile(int walfile, char *basedir, char *walname, bool segment_complete)
    {
        fprintf(stderr, _("%s: could not close file %s: %s\n"),
                progname, walname, strerror(errno));
+       walfile = -1;
        return false;
    }
+   walfile = -1;
 
    /*
     * Rename the .partial file only if we've completed writing the whole
@@ -270,7 +277,6 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
    char        current_walfile_name[MAXPGPATH];
    PGresult   *res;
    char       *copybuf = NULL;
-   int         walfile = -1;
    int64       last_status = -1;
    XLogRecPtr  blockpos = InvalidXLogRecPtr;
 
@@ -315,6 +321,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
    {
        fprintf(stderr, _("%s: could not start replication: %s\n"),
                progname, PQresultErrorMessage(res));
+       PQclear(res);
        return false;
    }
    PQclear(res);
@@ -341,9 +348,9 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
         */
        if (stream_stop && stream_stop(blockpos, timeline, false))
        {
-           if (walfile != -1)
+           if (walfile != -1 && !close_walfile(basedir, current_walfile_name, rename_partial))
                /* Potential error message is written by close_walfile */
-               return close_walfile(walfile, basedir, current_walfile_name, rename_partial);
+               goto error;
            return true;
        }
 
@@ -370,7 +377,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
            {
                fprintf(stderr, _("%s: could not send feedback packet: %s"),
                        progname, PQerrorMessage(conn));
-               return false;
+               goto error;
            }
 
            last_status = now;
@@ -421,14 +428,14 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
            {
                fprintf(stderr, _("%s: select() failed: %s\n"),
                        progname, strerror(errno));
-               return false;
+               goto error;
            }
            /* Else there is actually data on the socket */
            if (PQconsumeInput(conn) == 0)
            {
                fprintf(stderr, _("%s: could not receive data from WAL stream: %s\n"),
                        progname, PQerrorMessage(conn));
-               return false;
+               goto error;
            }
            continue;
        }
@@ -439,7 +446,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
        {
            fprintf(stderr, _("%s: could not read copy data: %s\n"),
                    progname, PQerrorMessage(conn));
-           return false;
+           goto error;
        }
        if (copybuf[0] == 'k')
        {
@@ -451,7 +458,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
            {
                fprintf(stderr, _("%s: keepalive message is incorrect size: %d\n"),
                        progname, r);
-               return false;
+               goto error;
            }
            continue;
        }
@@ -459,13 +466,13 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
        {
            fprintf(stderr, _("%s: unrecognized streaming header: \"%c\"\n"),
                    progname, copybuf[0]);
-           return false;
+           goto error;
        }
        if (r < STREAMING_HEADER_SIZE + 1)
        {
            fprintf(stderr, _("%s: streaming header too small: %d\n"),
                    progname, r);
-           return false;
+           goto error;
        }
 
        /* Extract WAL location for this block */
@@ -483,7 +490,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
            {
                fprintf(stderr, _("%s: received xlog record for offset %u with no file open\n"),
                        progname, xlogoff);
-               return false;
+               goto error;
            }
        }
        else
@@ -494,7 +501,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
            {
                fprintf(stderr, _("%s: got WAL data offset %08x, expected %08x\n"),
                        progname, xlogoff, (int) lseek(walfile, 0, SEEK_CUR));
-               return false;
+               goto error;
            }
        }
 
@@ -520,7 +527,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
                                       basedir, current_walfile_name);
                if (walfile == -1)
                    /* Error logged by open_walfile */
-                   return false;
+                   goto error;
            }
 
            if (write(walfile,
@@ -532,7 +539,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
                        bytes_to_write,
                        current_walfile_name,
                        strerror(errno));
-               return false;
+               goto error;
            }
 
            /* Write was successful, advance our position */
@@ -544,11 +551,10 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
            /* Did we reach the end of a WAL segment? */
            if (blockpos % XLOG_SEG_SIZE == 0)
            {
-               if (!close_walfile(walfile, basedir, current_walfile_name, false))
+               if (!close_walfile(basedir, current_walfile_name, false))
                    /* Error message written in close_walfile() */
-                   return false;
+                   goto error;
 
-               walfile = -1;
                xlogoff = 0;
 
                if (stream_stop != NULL)
@@ -577,8 +583,22 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
    {
        fprintf(stderr, _("%s: unexpected termination of replication stream: %s\n"),
                progname, PQresultErrorMessage(res));
-       return false;
+       goto error;
    }
    PQclear(res);
+
+   if (copybuf != NULL)
+       PQfreemem(copybuf);
+   if (walfile != -1 && close(walfile) != 0)
+       fprintf(stderr, _("%s: could not close file %s: %s\n"),
+               progname, current_walfile_name, strerror(errno));
    return true;
+
+error:
+   if (copybuf != NULL)
+       PQfreemem(copybuf);
+   if (walfile != -1 && close(walfile) != 0)
+       fprintf(stderr, _("%s: could not close file %s: %s\n"),
+               progname, current_walfile_name, strerror(errno));
+   return false;
 }

diff --git a/src/bin/pg_basebackup/streamutil.c b/src/bin/pg_basebackup/streamutil.c
index e5b3ee06c2805db3868442365b563ac6907ab0d3..96311e07b31f4460664982ca5458df9afe54998b 100644 (file)
--- a/src/bin/pg_basebackup/streamutil.c
+++ b/src/bin/pg_basebackup/streamutil.c
@@ -143,6 +143,17 @@ GetConnection(void)
 
        tmpconn = PQconnectdbParams(keywords, values, true);
 
+       /*
+        * If there is too little memory even to allocate the PGconn object
+        * and PQconnectdbParams returns NULL, we call exit(1) directly.
+        */
+       if (!tmpconn)
+       {
+           fprintf(stderr, _("%s: could not connect to server\n"),
+                   progname);
+           exit(1);
+       }
+
        if (PQstatus(tmpconn) == CONNECTION_BAD &&
            PQconnectionNeedsPassword(tmpconn) &&
            dbgetpassword != -1)
@@ -154,8 +165,11 @@ GetConnection(void)
 
        if (PQstatus(tmpconn) != CONNECTION_OK)
        {
-           fprintf(stderr, _("%s: could not connect to server: %s"),
+           fprintf(stderr, _("%s: could not connect to server: %s\n"),
                    progname, PQerrorMessage(tmpconn));
+           PQfinish(tmpconn);
+           free(values);
+           free(keywords);
            return NULL;
        }